We look at the division of 15693845 by 91 
The aim is to understand the frequency of 91 in 15693845.

Going ahead to step 1:
If we divide 1 by 91, we get 0 and a remainder of 1.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we subtract 0 from 1, we get 1.
Append the next digit (5) from the dividend to 1 and continue with: 15 / 91

Advancing to step 2:
91 can be fit into 15 0 times, resulting in a remainder of 15.
Put 0 as the next digit of the answer. 
Result so far: 0.0
If we subtract 0 from 15, we get 15.
Grab the next digit (6) from the dividend, add it to 15, then carry on: 156 / 91

Advancing to step 3:
If we divide 156 by 91, we get 1 and a remainder of 65.
Put 1 as the next digit of the answer. 
Result so far: 1.0
If we subtract 91 from 156, we get 65.
Append the next digit (9) from the dividend to 65 and continue with: 659 / 91

Step 4:
91 can be fit into 659 7 times, resulting in a remainder of 22.
Use 7 as the next digit of our solution. 
Result so far: 17.0
The remainder is 22 after subtracting 637 from 659.
Fetch the next digit (3) from the dividend, attach it to 22 and continue: 223 / 91

Advancing to step 5:
91 can be fit into 223 2 times, resulting in a remainder of 41.
The number 2 becomes the next digit in our result. 
Result so far: 172.0
Deduct 182 from 223 and we're left with 41.
Include the next digit (8) from the dividend after 41, then repeat: 418 / 91

Going ahead to step 6:
91 goes into 418 4 times with a remainder of 54.
Write down 4 as next digit of the result. 
Result so far: 1724.0
If we take 364 away from 418, we end up with 54.
Grab the next digit (4) from the dividend, add it to 54, then carry on: 544 / 91

Step 7:
91 goes into 544 5 times with a remainder of 89.
Write down 5 as next digit of the result. 
Result so far: 17245.0
If we subtract 455 from 544, we get 89.
Include the next digit (5) from the dividend after 89, then repeat: 895 / 91

Going ahead to step 8:
91 goes into 895 9 times with a remainder of 76.
The next digit of our result is 9. 
Result so far: 172459.0
The remainder is 76 after subtracting 819 from 895.
Since there are no more digits in the dividend, we add a zero to the remainder making it 760, and continue the process.

Going ahead to step 9:
When dividing 760 by 91, we get 8 with a remainder of 32.
Record the quotient 8 as the next digit in the result. 
Result so far: 172459.8
Subtracting 728 from 760 leaves us with 32.
Since there are no more digits in the dividend, we add a zero to the remainder making it 320, and continue the process.

Advancing to step 10:
If we divide 320 by 91, we get 3 and a remainder of 47.
Put 3 as the next digit of the answer. 
Result so far: 172459.83
Subtract 273 from 320 to get 47.
Since there are no more digits in the dividend, we add a zero to the remainder making it 470, and continue the process.

Going ahead to step 11:
If we divide 470 by 91, we get 5 and a remainder of 15.
Record the quotient 5 as the next digit in the result. 
Result so far: 172459.835
If we subtract 455 from 470, we get 15.
Since there are no more digits in the dividend, we add a zero to the remainder making it 150, and continue the process.

Moving on to step 12:
91 can be fit into 150 1 times, resulting in a remainder of 59.
Write down 1 as next digit of the result. 
Result so far: 172459.8351
The remainder is 59 after subtracting 91 from 150.
Since there are no more digits in the dividend, we add a zero to the remainder making it 590, and continue the process.

Advancing to step 13:
If we divide 590 by 91, we get 6 and a remainder of 44.
Write down 6 as next digit of the result. 
Result so far: 172459.83516
If we take 546 away from 590, we end up with 44.
Since there are no more digits in the dividend, we add a zero to the remainder making it 440, and continue the process.

Step 14:
The number 91 fits into 440 4 times, leaving a remainder of 76.
Put 4 as the next digit of the answer. 
Result so far: 172459.835164
Deduct 364 from 440 and we're left with 76.
Since there are no more digits in the dividend, we add a zero to the remainder making it 760, and continue the process.

Moving on to step 15:
91 can be fit into 760 8 times, resulting in a remainder of 32.
Write down 8 as next digit of the result. 
Result so far: 172459.8351648
The remainder is 32 after subtracting 728 from 760.
Since there are no more digits in the dividend, we add a zero to the remainder making it 320, and continue the process.

Moving on to step 16:
91 goes into 320 3 times with a remainder of 47.
Put 3 as the next digit of the answer. 
Result so far: 172459.83516483
If we take 273 away from 320, we end up with 47.
Since there are no more digits in the dividend, we add a zero to the remainder making it 470, and continue the process.

After the division, we end up with 172459.83516483 and a remainder of 4.7e-08.